S
M
T
W
T
F
S
30
90°
77°
31
92°
77°
1
92°
76°
2
91°
76°
3
91°
75°
4
90°
76°
5
91°
76°
6
91°
75°
7
90°
76°
8
91°
76°
9
91°
75°
10
90°
75°
11
92°
74°
12
90°
76°
13
91°
75°
14
91°
76°
15
90°
76°
16
89°
75°
17
90°
76°
18
91°
75°
19
91°
75°
20
90°
74°
21
90°
75°
22
89°
75°
23
89°
74°
24
88°
73°
25
87°
71°
26
86°
73°
27
86°
73°
28
87°
72°
29
86°
72°
30
86°
73°
1
87°
73°
2
89°
72°
3
89°
74°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Sanibel
Sanibel's September 2026 forecast shows daily high temperatures ranging from 86° to 92°, with overnight lows between 71° and 77°. The average high for September is 90° with an average low of 75°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how September weather will actually feel in Sanibel. See also: October | November | December.
